Rainbow Dash is confident and brash. She has no problem talking about her abilities. When a new pony comes into town boasting that she was the best, Dash says they already have a pony to be the best so they didn’t need her. She laughs it off though when Applejack gives her a harsh look.
She’s also always ready to a race. Like when she saw Twilight Sparkle and Fluttershy racing around to find Willamina. Rainbow Dash took it as they were racing even when they didn’t have a chance to answer her they weren’t. Racing is an easy distraction to her, and makes her blind to the problems at hand. This was clear when her griffin friend only had to challenge her to a race to make her forget everything else.
In this respect she can be very air headed. She doesn’t really see a problem with only focusing on what matters to her and isn’t afraid to tell others when they annoy or bore her. This is where her brashness comes in. She isn’t terribly rude though, and can hold back with just making a face instead, or laughing. This happens when she laughs at Twilight for racing.
However, when others ask for her help, she is willing to give it. This is clear when she is willing to destroy Applejack’s barn when she asks her to. She may complain that she doesn’t like the task, but she tries to be a good sport. This can be seen when Rarity is trying to make a dress for Rainbow Dash, but she keeps fidgeting. She had chances to escape, but she doesn't because had been asked to do this, showing she's capable of keeping to her word.
Rainbow Dash can become extremely nervous in the face of competition. This can make her trip up at times, like when she competed in the young fliers competition. She became really scared though because flying is her entire life. Since it means so much to her, it has a really big impact on her. Her cutie mark represents her inner talent that makes her different from all other ponies, and this is a rainbow bolt from a cloud. It represents her need for speed and her love of competition. Considering everything, it's no surprise that she wants to become one of the Wonder Bolts; that being her life long dream that's she's been working so hard to accomplish. It’s when this dream comes into play that she can trip up on her own two feet. She works really hard though, trying to perfect her signature moves at all times. Because of her admiration for them, she will do just about anything to get their attention. She will even try to catch things that she clearly can’t hold, like a large statue that fell over at the Grand Galloping Gala. Even though her intentions were good, She just made a bigger mess because she stumbled around with the weight on her back.
She can also seem lazy at times, but it’s only when she doesn’t want to do things. This is shown when she took a nap in the apple orchard instead of helping her friends. If it isn’t important to Rainbow Dash, she doesn’t want to do it. This is shown when she seems to take long breaks while she's doing her job, but that's only because she feels she can do it in no time flat, so why worry about 'when' it's done? This is clear when Twilight Sparkle first finds her being lazy in the clouds. Rainbow Dash was put in charge of the weather during the Summer Sun Celebration and Twilight Sparkle was there to make sure she did it. Since the main task of the weather pony was to clear the sky, and it wasn’t clear at all, Twilight prodded her into doing it by saying that the Wonder bolts would never accept a pony that couldn’t keep the sky clear for a day. Dash responded by saying she could do it in 10 seconds flat, which she did! This shows that Rainbow Dash is good to her word.
Her element of harmony is Loyalty, and it is her biggest strength. She is always willing to put her friends over herself, as shown in the first episode of season one when she refused the offer of the “shadow bolts” to become their leader because she had to help her friends first. She may be brash, seem like she’s rude, but she never means to hurt any pony. This can be seen when she frightens the ponies at the Nightmare Night. She’s only doing it in good fun, even if it can seem that she’s over doing it and just being a bully. That wasn’t why she was doing it. It was supposed to be in all good fun.
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It all started one day at flight camp, when I alone stood up against Fluttershy's bullies by challenging them to a race! At the gate, it was nothing but tension, but then I blasted off ahead of them! I'd never flown like that before! the speed the adrenalin, I liked it! A lot. But then one of the bullies cut me off and sent me spinning! I was determined not to let that stop me though and ZOOMED off even faster, because it turns out the only thing that I liked better then flying fast, was winning! I went faster and faster, and then suddenly, BAM! I went so fast that I broke the light barrier and made a Sonic Rainboom! Most people had thought it was just a legend, but I proved it real! It was when I made the impossible happen, when I found my love of racing, that this awesome cutie mark appeared on my flank~